This invention relates to fire sprinkler apparatus and more particularly to the combination of a reducer having a frangible seal used during initial testing of the apparatus and a tool for insertion into the coupling for forcibly shattering the seal after completion of the testing so that a sprinkler head may be operatively connected to the coupling.
In fire sprinkler systems used in commercial buildings, office buildings, industrial buildings, warehouses and the like, a main water supply pipe is disposed above the ceilings in such buildings, the main pipe having a plurality of drop pipes connected thereto by means of respective tee joint coupling. Conventionally, the drop pipe initially extends below the ceiling and has a coupling at the end thereof, the coupling having a conventional pipe plug inserted therein to prevent water from flowing out the coupling during the initial testing of the system. During the initial testing phase water is supplied to the main pipe and pressure and flow checks are made prior to installation of the sprinkler heads. After the testing phase the drop pipe must be cut so that the coupling can be disposed at the ceiling level and the sprinkler heads attached thereto. This first requires removal of the plug to permit the water that has accumulated in the vertical drop pipe to be drained. A measurement must then be made to determine the distance from the ceiling to the bottom of the coupling. The drop pipe is then disconnected from the tee coupling and shortened by cutting off the upper end of the drop pipe by the amount of the previously made dimension. The cut portion of the pipe must then be rethreaded and connected back into the tee coupling so that the coupling is substantially at the elevation of the ceiling. The sprinkler head is thereafter attached to the coupling.
Not only is this procedure time consuming, and thus costly, especially where there are a substantial number of such drop pipes, since each pipe must be rethreaded and doped and, additionally each plug must be doped prior to initial insertion into the coupling. Furthermore, a number of other problems may result. For example, if a plug swells it may be difficult to remove from the coupling prior to disconnection of the drop pipe and, since conventional plugs have square heads, if the edges of the head become "stripped" it may be necessary to remove the coupling from the drop pipe and replace it with a new coupling prior to making the measurement from the ceiling. Another problem occasionally results when plugs are not readily available when the test is to be made. In these instances delays result or if a sprinkler head is utilized in place of a plug during the testing phase, subsequent use of the head may result in leakage. Another inconvenience which occurs with the prior art system is that since the length of the drop pipe is substantial, when the plug is removed from the coupling, or the coupling is removed from the pipe in those instances where the plugs may have swelled, a substantial amount of water may drain, and this may cause obvious problems where the sprinkler system is being retrofit into existing buildings.